<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>登录界面</title>
    <link rel="stylesheet" href="css/login.css">
    <script src="js/login.js"></script>
</head>
<body>
    <div id="bg"></div>
    <form action="" onsubmit= "return sub()">
        <div><h2>login!</h2><hr></div>
        <div id="log">login</div>
        <label>
            <input type="text" name="aa" id="aa" placeholder="Username">
        </label>
        <div id="error1">请输入用户名</div>
        <label>
            <input type="text" name="bb" id="bb" placeholder="Password">
        </label>
        <div id="error2">请输入密码</div>
        <input type="submit" value="login" id="submit">
    </form>
</body>
</html>